Jeff Ward, chief scientist of forestry and horticulture at the Connecticut Agricultural Experiment Station, measures the height of Yellow Groove bamboo plants for comparison next year before treating the invasive species in Woodbury, Thursday, Nov. 30, 2012.
Photo: Michael Duffy

Greg Cerne of the Connecticut Agricultural Experiment Station measures the height of Yellow Groove bamboo plants for comparison next year before treating the invasive species in Woodbury, Thursday, Nov. 30, 2012.
Photo: Michael Duffy

WESTPORT -- Talk to a person with a neighbor growing a stand of bamboo on the property line, and you're going to hear some words that can't be printed in this newspaper.

"It's a nightmare," said Priscilla S. Weadon, of Westport, whose neighbor on her street planted bamboo a few years back. Now it's invading her property, and she's at her wit's end.

"Once you're aware of it, you'll see it everywhere," she said. "They're popping up all over the place in my yard. You can't kill it. I've used some really powerful chemicals. Didn't work."

Westport, like dozens of towns and cities in Connecticut, is home to several astonishing mini-forests of yellow groove bamboo. If your only experiences with the plant are the torches at your neighbor's tiki party, you're in for a jaw-dropping experience.

Powerful plant

In a mature stand, the stems, or culms, are between two and three inches in diameter. Their density is sufficient to keep a second-grader from squeezing through. The layer of delicate leaves begins at about the 6-foot level and continues up to a height of 35 feet or more.

The plant produces a very infrequent crop of seeds, so its primary strategy of spreading is though its rhizomes, the underground stems that are the source of the plant's nightmarish reputation.

Rhizomes fan out inexorably to claim new turf. In essence, a stand of bamboo is a single plant because all of the rhizomes are interconnected. Barriers such as sidewalks, fences and stone walls offer little resistance.

Rickel's group is trying to get bamboo banned in Connecticut. Her infestation was severe enough to convince Seymour's Board of Assessment Appeals to reduce the assessed value of her home by about 13 percent.

"The shoots grow right through asphalt," she said. "The plant is exponential. The first two or three years isn't bad, but by year five it's a problem. By year 10 or 15, it's taking out your whole street."

Another horror story came from Robin Arcarese, of Bozrah, in eastern Connecticut.

"Just this spring, I was pulling into my driveway and I said to myself, `What's that growing out of my roof?' " she said. "It was my neighbor's bamboo, which had grown behind my siding and out the roof."

Not an `invasive'

In spite of bamboo's almost unearthly growth rate, it's not on the state's list of invasive species, nor is it likely to be anytime soon, experts say.

This is because, although it's a huge headache for some homeowners, it doesn't seem to be attacking natural habitats to any significant degree, and its effect on native plants and animals is all but nonexistent.

"Right now, bamboo isn't meeting enough criteria to be considered as even potentially invasive," said Donna Ellis, senior extension educator and co-chairwoman of the Connecticut Invasive Plant Working Group. "This is not to say that it isn't causing problems for homeowners, particularly along property lines, but because of the nature of where it's growing, it's not posing a threat to the natural habitat."

There are more than 100 plants on the state's list of invasive plants, many of which you see every day, from the Norway maple to the beach rose. It's illegal to cultivate, purchase, sell or transplant any of the plants on the list.

Still, yellow-groove bamboo has been banned or limited elsewhere, including in several communities in Delaware, New York, Maryland, Pennsylvania and Florida and even in Australia. In 2011, Sag Harbor, N.Y., enacted a ban, but it was quickly repealed.

"The problem isn't with bamboo, it's with neighbors," said Mike Johnson, who grows bamboo professionally at his Summer Hill Nursery in Madison, which sells plants wholesale to other nurseries and garden centers.

Johnson said that whenever he sells bamboo, he also makes sure that the buyers are aware of what they're dealing with.

"I also sell the barrier to them at cost," he said. "But when you mention `barrier,' some people won't hear of it. I've had cases in which people have said, `I don't want a barrier -- I just want to get back at my neighbor.' "

Indeed, in East Lyme, Daniel and Sally Wade are in a long-running spat with a cantankerous neighbor. While neighborly disputes are common everywhere, the Wades are now dealing with a growth of bamboo that the neighbor planted along their property line.

"He planted this thing as a weapon to destroy our property," Daniel Wade said. "Then he installed a rhizome barrier on his side of the bamboo, but not on ours."

Johnson said that when properly handled, bamboo is a beautiful plant that creates an inexpensive and fast-growing privacy screen. He also said that his sales have doubled since stories about the bamboo infestations began appearing in the news a couple of years back.

"The barrier that we sell is 60 mil (1.5 mm) high density polyethylene plastic sheet that goes down 30 inches," he said. "The rhizomes aren't going to get through that."

Knocking it back

The sooner you attack bamboo infestation, the better.

In Woodbury on Thursday, Ward was with a crew of his fellow Experiment Station plant scientists to conduct an early morning attack on an eighth-acre stand of yellow groove in a town park. After about 45 minutes, the growth surrendered to their power brush cutters. But Ward said that the stand will need continued treatment and monitoring in the coming year or two before victory will be complete.

"We'll come back out here again in June to cut it down again, and we'll probably have to spray it in the late summer."

Ward said that to be effective, a herbicide such as Scott's Roundup has to be applied in the late summer. This is when the flow of nutrients in plants switches from up to down.

"Some people say that this strategy won't work," Ward said. "But other people say that it does work. I don't have a horse in this race, I'm just trying to find out the most cost-effective way to deal with this plant."

The other option, and far more expensive, is to dig out the rhizomes with a power shovel. This entails sifting through the dirt to extract all of the rhizomes and burning them so as not to be left with a pile of soil that will cause another bamboo infestation.

Another complication is that bamboo problems are usually along property boundaries, which means stone walls, fences, driveways, sewer pipes, water lines and such are often in the way of digging.

The Experiment Station is growing bamboo at all three of its farms to determine growth rates and control methods.

The `great new plants'

Bamboo is the fastest-growing plant on Earth; whether that's a good or a bad thing depends on which side of the fence you're on. Its supporters say that globally, it's indispensable, providing fibers and building materials from a renewable resource. Strong and flexible, it's being used to construct thousands of new earthquake-resistant homes in Costa Rica. The plant has scores of other uses, such as basketry, food, fishing poles, medicine and even musical instruments.

But in Connecticut, it's use as a timber or fiber crop has yet to be exploited.

Kathleen Nelson, of Sherman, used to own a small nursery, part of an industry that she has come to realize has been the cause of problems with a number of plants, bamboo included. Now, she leads a group called Mad Gardeners. Its primary focus is the dreaded mile-a-minute vine, but in doing her research, she said that she's come across scores of unwanted stands of bamboo.

"We tend to think linearly, but you really have to think exponentially with bamboo because that's how it grows," she said. "After five years, you think you're fine, and then whammo."

She said that for too long, nurseries have been encouraging use of new plants, many of which came from Asia and which soon became difficult to manage.

"Back in the 1980s, it was `show me the great new plants,' " Nelson said. "Now we know that these `great new plants' are scary. Now I say, `show me the great old plants, the native plants.' "